The network-oriented application services paradigm is becoming increasingly common for scientific computing. The popularity of this approach can be attributed to the numerous advantages to both user and developer provided by network-enabled mathematical software. The burden of installing and maintaining complex systems is lifted from the user, while enabling developers to provide frequent updates without disrupting service. Access to software with similar functionality can be unified under the same interface. Remote servers can utilize potentially more powerful computing resources than may be available locally. We discuss some of the application services developed by the Mathematics and Computer Science Division at Argonne National Laboratory, including the Network Enabled Optimization System (NEOS) Server and the Automatic Differentiation of C (ADIC) Server, as well as preliminary work on Web access to the Portable Extensible Toolkit for Scientific Compuoting (PETSc). We also provide a brief survey of related work.